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arXiv · 1806.09400

A pathway towards proper modeling of physical properties

Abstract

Theoretical concepts in condensed matter physics are typically verified and also developed by exploiting computer simulations mostly in simple models. Predictions based on these usually isotropic models are often at odds with measurement results obtained for real materials. On the other hand, all-atom simulations are complex and time-consuming. In this paper, we formulate a new strategy for effective molecular modelling, which properly reflects properties of real particles by using quasi-real molecules of simple but anisotropic architecture and identifying the applicable range of intermolecular interactions for a given physical process or quantity. As a demonstration of our method capabilities, we solve an intriguing problem within the density scaling idea that has attracted attention in recent decades due to its hallmarks of universality. It demonstrates that the new strategy for molecular modelling opens broad perspectives for simulation and theoretical research, for example, into unifying concepts in the glass transition physics.

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K. Koperwas, A. Grzybowski, M. Paluch. 2018-06-25. A pathway towards proper modeling of physical properties. https://doi.org/10.1063/1.5050330

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